Motorized fruit and vegetable juicers are well known. Most conventional domestic fruit and vegetable juicers are single speed machines although some have two or three speeds. A motorized fruit and vegetable is depicted in the applicant's PCT application PCT/AU2004/0007828.
Multi speed fruit and vegetable juicers have been developed because the rotating grader is more effective at higher speeds with harder fruits and vegetables and more effective at lower speeds with softer fruit and vegetables. However, many consumers are unaware of the relationship between motor speed and fruit or vegetable hardness. Further, fruit and vegetable juicers known in the prior art have lacked displays which assist the user in selecting the appropriate motor speed.
Motorized centrifugal juicers use a cutting disk with angled strainer basket for continuous juicing. The plant material is pushed down against the cutting disk and then forced against the angled basket. The vegetable pulp hits the angled basket and centrifugal force pulls the juice out of the shredded plant material. In order to discharge pulp from the spinning basket effectively (and for the processing of harder fruits and vegetables) this type of juicer needs to spin relatively quickly.
Although high motor speeds reduce the effort for juicing hard fruits and vegetables, higher motor speeds are unnecessary for juicing softer fruits like watermelon and citrus. Higher motor speeds are associated with increased airflow that results in leakage, as juice will tend to accompany air escaping through the gaps in the case of the juicer. In addition to leakage, increased motor speeds can also generate excess foam that sits on top of the juice and are also associated with increased noise levels.